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Post by edireland on Aug 27, 2013 9:17:34 GMT 9.5
[we need] sufficiently high separation factors to make pyroprocessing practical for LWR use. FLUOREX is probably the best reprocessing technology that is practical for LWRs ... Jagdish spoke of electrolysis of used LWR fuel in a chloride melt, as has been discussed elsewhere on BNC. Here, the first, majority deposit on the cathode is the still-enriched uranium, ready for re-enrichment for LWR use. The second, minor deposition is the U-Pu amalgam in the cadmium cathode, appropriate for reuse in fast reactors. This seems to me like "sufficiently high separation factors to make pyroprocessing practical for LWR use". Am I missing something? Fast reactor fuel is useless when we will likely not have a squadron fleet of fast reactors to use it. Plutonium and uranium will have to be recycled in light water reactors. (At best maybe RMWRs) FLUOREX is the best process that can produce LWR usable materials. In that electrolysis process you will end up with a fission product contaminated metallic product which is of no use in an LWR.
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Post by edireland on Aug 26, 2013 23:04:52 GMT 9.5
And it costs an absurd amoutn of money for absolutely no benefit over more traditional transport technologies.
Its one of those nonsensical pipe dreams that will never go anywhere.
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Post by edireland on Aug 22, 2013 18:23:33 GMT 9.5
Cyril, They used Pu239 and Pu238 from weapons but common radiation from NPP blow up is Pu239, Pu240 and Pu241 , these produce americium241 and about a dozen other isotobes that are hazadouse. The study has very little to do with NPP radiation, it takes a while but study Pu239-240-241 and all their daughter products and their daughter products and you will gasp at the hazards. Pu-239 primarily decays by alpha emission, producing.... U-235. Which has a far longer half life than the Plutonium does and has radiotoxicity that is swallowed up by its chemical toxicity. Pu-240 primarily decays by alpha emission, producing a very long lived isotope U-236. Not quite as long lived as U-235 is but still very long lived. Only Pu-241 decays to something nasty, but that is a very small fraction of reactor grade plutonium. Which has a half life It is hard to find studies on some daughter products to know how hazardest they are. For your infermation when looking into it is the shorter the half life the more hazardest it is. All so most studies by pro-nuclear in air breathed in to lungs always assumes that radiation is equaly distributed in the air showing it will take huge volums of air or water to be ahazard. This is why the antinukes and pro-nukes are so far apart in evaluating hazard from NPP. So we have a catastrophic core breach accident and yet the gaseous fission products are not heated in the slightest and thus do not column, instead forming a very very thick cloud around the plant? The only major threat is the short lived radioiodine isotope which is protected against by Saturated KI solution (or tablet based) prophylaxis which is very cheap. (I once calculated you could buy the entirety of the UK the requisite 90 day course for a few tens of millions of dollars, could be stockpiled for use in case of a reactor accident)
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Post by edireland on Aug 22, 2013 18:13:36 GMT 9.5
Existing processing is a continuation of plutonium extraction for weapons. For reactor use we should adopt pyroprocessing using chloride volatility and electrolysis. Solution based processing involves too much of fluids which will leak later. High temperature processing leaves mostly solids after cooling for some time, which can be put away till required again. Come back when you obtain sufficiently high seperation factors to make pyroprocessing practical for LWR use. FLUOREX is probably the best reprocessing technology that is practical for LWRs at the present time, as it avoids the conversion steps for most of the uranium, allowing reduced cost re-enrichment (potentially on site at the reprocessing plant).
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Post by edireland on Aug 22, 2013 1:29:12 GMT 9.5
Plutonium Nitrate would exist in nature in certain circumstances, such as a leak from a reprocessing plant.
But in the case of a catastrophic chernobyl esque core accident it is correct that it would not.
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Post by edireland on Aug 14, 2013 7:16:17 GMT 9.5
Oh god, not this thing again. Its rubbish.
The report is shot through with lies and mistatements and drastically understates the cost. He also overstates the energy cost of HSR by almost an order of magnitude. TGV Duplex would do the 400 miles in ~2hrs with an energy cost of 20kWh per seat. So about $1-2.
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Post by edireland on Aug 10, 2013 6:53:08 GMT 9.5
AGR overcame the carbon monoxide reaction problem by using a re-entrant system to cool th graphite to the reactor inlet temperature rather than the outlet temperature.
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Post by edireland on Aug 4, 2013 7:33:05 GMT 9.5
This is just a piece about America panicking that it won't have an effective monopoly on cheap enrichment in the future. I hope it leaks out, because otherwise everyone will be left in hoc to the Americans for energy.
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Post by edireland on Aug 4, 2013 7:26:31 GMT 9.5
Are you in a hurry to reprocess? If you leave it 15 years or more before sending it to the "fine process" plant. The radiolytic issue will be far less evident than it would be after the normal 5 year cooling system.
And Sr-90 and Cs-137 are not that valuable because we will be buried in them.
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Post by edireland on Aug 4, 2013 1:43:07 GMT 9.5
Well you can just wait for a few more years and feed said pyroprocessing waste to a modified aqueous process if you want. The effective lack of criticality concerns would be a major benefit in cost terms.
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Post by edireland on Aug 2, 2013 5:26:31 GMT 9.5
If we have a Carrington event then you have far bigger problems than a handful of reactor meltdowns.
Millions of dead from serious civilisational damage.
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Post by edireland on Aug 1, 2013 4:11:22 GMT 9.5
I know of four light water meltdowns using western designs, TMI and the three units at Fukushima.
But if you count all LWRs that have operated in the west then the count is enormous, since you have to include military reactors. 254 reactors have been or are operated by the USN at sea, no reactor accidents are recorded. 31 reactors have been or are operated by the Royal Navy at sea, no reactor accidents are recorded. ~20 reactors operated (or have been operated) by the Marine Nationale in France, then the enormous french civil reactor programme.
The list goes on and the count gets larger and larger.
If you put modern designs like ESBWR through the conditions at TMI or Fukushima then catastrophic core damage is almost impossible. (I assume the emergency services in Japan could have found a 9hp water pump within 72 hours?)
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Post by edireland on Jul 24, 2013 7:26:14 GMT 9.5
Well a couple of reactors at Bruce NPP stayed at 60% reactor load (I believe the minimum sustainable load) throughout a complete blackout that would normally have required a shutdown simply by dumping steam directly to the condensers, only spinning the turbines with enough steam to cover plant power requirements.
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Post by edireland on Jul 23, 2013 7:09:09 GMT 9.5
Low temperature hydrogen electrolysis. (It has no thermal cycling and with proper control there is little issue with compressors being damaged by spooling up and down).
Additionally you don't have to power down systems completely. So you can keep things like SSAS banks hot but only at fractional output.
Smart meters are a great social evil because they will damage the freedom of the poorer members of society.
EDIT:
The marginal costs of nuclear steam are so low that you could just bleed steam to an accumulator during times of low demand and use it for a variety of secondary industrial tasks (including MED-TVC)
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Post by edireland on Jul 23, 2013 6:51:51 GMT 9.5
Still far too expensive.
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Post by edireland on Jul 21, 2013 0:15:17 GMT 9.5
People don't tend to live in deserts. The power lines would be jugulars stretching from industrial centres into the desert. Desert that would have to be garrisoned with vast armies of ground troops (especially in the Europe/Sahara scenario) that would effectively have to do Western Sahara-style fortifications on an unprecedented scale.
It would be expensive and would cause all sorts of othher problems.
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Post by edireland on Jul 18, 2013 1:59:45 GMT 9.5
Remember too that any nuclear system will also need gas back up, as the generation side must be able respond as quickly as the demand side. Nuclear plants are big, slow Rankine cycles, just like coal plants and they can't ramp fast enough to meet all the demand in a day.
Read more: bravenewclimate.proboards.com/index.cgi?board=bncblogposts&action=display&thread=416#ixzz2ZJy8nyzs
Why does it need gas backup? The marginal cost of operating a modern BWR (see an ESBWR) in terms of staffing and fuel comes out at about one US cent per kWh. One. That is so cheap that it would be better to leave the plant running at full throttle at all times and when you have spare capacity, route the electricity into some insanely energy intensive process that doesn't require large capital cost equipment. For instance very cheap alkaline electrolysers could easily breach $1/kg for hydrogen using one cent per kWh electricity. I imagine you could easily sell such hydrogen at that price, additionally there are things like Solid State Ammonia Synthesis to consider, especially since the top of the peak is only required for 10% of the day, meaning that your "power sink" can run 90% of the time. Since nuclear plant is cheaper per GWe than solar is for the same average output it is cheaper to build a 100% nuclear system and simply use electrolysers or similar equipment to soak up the "waste" electricity. Gas backup would be unnecessary, and since the electrolysers would be at room temperature and can thus go from 100% to 0% output in seconds, spinning reserve would also be redundant.
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Post by edireland on Jul 16, 2013 19:37:01 GMT 9.5
Well since I would assume the calcium silicate would be introduced in coastal waters (since that is where we have access too) it would seem reasonable that most of the resulting carbonates would be laid down in shallow water.
While carbonates that reach the abyssal plain tend to redissolve we have to consider the entire system as a whole, and it appears that adding calcium salts to the ocean will cause calcium salts to exit the oceanic system somewhere, and since the least soluble salts tend to be carbonates this is probably the form which they will be laid down in. Additionally this process can be encouraged by the deployment of biorock style equipment provided that sufficient low cost energy is available - you could probably even cause the biorock to form ready made polders if you wanted to.
While concrete does initially harden by hydration old concrete will very gradually carbonate, while it is true that if you ground up new concrete you would not find many carbonates, most ground up concrete tends to be decades old and has undergone significant carbonation, drastically reducing your carbon dioxide emissions saving.
Additionally the amount of concrete being ripped up in any one year is a rather small fraction of the amount being manufactured, so it probably won't make any significant difference.
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Post by edireland on Jul 16, 2013 17:12:31 GMT 9.5
Many liquidators have died already because it was 27 years ago. Considering the relatively low life expectancy in the former soviet union you would have expected a large fraction of them to die anyway.
The UNSCEAR report does not mention hordes of deformed children, but then they are presumably paid shills of the nuclear industry who are trying to silence the news of the magnitude of the horror unleashed?
Remember that by now even the Strontium and Caesium threat is receding since the activity of the primary isotopes will have fallen by half.
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Post by edireland on Jul 16, 2013 11:20:04 GMT 9.5
Nope, we can't hide it there either. The cycle time for "intermediate oceanic water" is about 300 years, and as John O'Neill pointed out, the hotter it gets in the future, the faster the ocean will outgas. Far from being a solution, dumping CO2 deep into the oceans would create a timebomb. You misunderstand, the introduction of the calcium silicate will increase the pH of the ocean, causing the less soluble ions to precipitate out as insoluble salts. The least soluble common cations in seawater are calcium and magnesium and the least soluble common anion is carbonate. Therefore the bulk of the precipitated material is either calcium or magnesium carbonate. The net effect is carbon dioxide moves out of the atmosphere and into the storage tanks downstream of the cement kilns. Limestone also moves to the bottom of the sea but thats not really important. One way to reduce CO2 emissions from the making of new cement, is to use the fine material produced when recycling concrete. If ordinary concrete made with Portland cement is heated, it weakens and may be crushed to recover its aggregate. Because the fines have already lost their CO2 during the manufacture of the cement, the reconstituted Portland cement could be clinkered with much lower emissions. Ironically, high-alumina cement (which is fused) can be made fresh in an electric furnace unlike Portland (which is clinkered), but is stronger after heating than Portland cement, so its concrete is harder to recycle. Problem is that that cement has already cured once and thus cannot cure again without being refired, so you don't really gain anything. (Concrete actually slowly absorbs carbon dioxide over the years after it cures, becoming closer and closer in composition to a mix of calcium carbonate and silica) Using it as aggregate on the hand is useful but not going to save that much energy. The carbon dioxide trapped from the kilns can be used as a concentrated feedstock for various things including plastics, synthetic fuels or even food (via Pruteen and livestock). It sets a hard upper limit on the cost of carbon dioxide capture. (Since to start with you can sell the cement and allow it to soak up carbon over decades while its part of a building).
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Post by edireland on Jul 15, 2013 22:46:02 GMT 9.5
I don't just mean apartment blocks, I am referring to built up low rise areas composed of detached and semi detached houses. If you freeze the ground bad things happen, and ground source pumps tend to have far high pricetags than air source systems, and the latter tend to be easier to repair. (No hunting for a buried leak in a ground loop).
Air to Air pumps can supposedly get COPs of 5.
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Post by edireland on Jul 15, 2013 21:23:22 GMT 9.5
The ocean can effectively be used as a giant carbon dioxide scrubber. One way to trap carbon dioxide is to make cement like materials from calcium carbonate using electric heat (tapping off the pure stream of carbon dioxide made by the process) and then dump it in the sea.
The alkali component will absorb carbon dioxide and fall to the sea bottom as calcium carbonate. Its probably cheaper in the long run than traditional direct trapping methods, assuming we can get low enough cost energy to do the job.
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Post by edireland on Jul 15, 2013 20:43:41 GMT 9.5
Ground Source Heat Pumps have serious problems in high density areas like most of the UK. During the winter they will likely freeze the ground solid.
Meanwhile direct cycle air-to-air heat pumps get high COPs due to low outlet temperatures and are an awful lot cheaper.
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Post by edireland on Jul 14, 2013 8:58:25 GMT 9.5
Plants melt down because of idiots.
And the figures that generate enormous numbers of health effects from Chernobyl just use the difference of the death rates between the 80s and 90s. Because Chernobyl makes you more likely to drink yourself to death or die in a car accident.
All reasonable figures show a few hundred deaths from Chernobyl.
And this is before we count all the people with deformities that are wheeled out by locals for the benefit of "journalists" who go around asking where all the people with deformities from Chernobyl are and pay for the privilege of meeting them.
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Post by edireland on Jul 13, 2013 20:06:19 GMT 9.5
Presumably they have a giant tank of molten salt that allows heat to be "stored" on a diurnal basis.
Still doesn't help with seasonal variations.
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Post by edireland on Jul 12, 2013 0:01:21 GMT 9.5
The concealing authority could just arrange for a couple of tonnes of KI to accidentally fall into a water treatment settling tank and then not tell anyone.
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Post by edireland on Jul 10, 2013 8:38:10 GMT 9.5
Denmark's total wind energy supply is irrelevant, since it has massive energy transfers across its borders to Norway and Germany both of which are reliant on things that are not non-hydro renewables.
It essentially cheats. Cut all the power lines in and out of Denmark and see how well it does.
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Post by edireland on Jul 9, 2013 22:16:42 GMT 9.5
Radon is a specific threat because it likes to decay inside your lungs after you breathe it in, producing radioactive daughter nuclides that decay eight more times in direct contact with the interior tissue of your lungs. Including some very nasty gamma and alpha decays that will do serious tissue damage.
Radon is almost alone in posing this kind of threat. Fission product waste will not do this.
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Post by edireland on Jul 9, 2013 4:40:27 GMT 9.5
In theory you don't even need a Uranium enrichment plant if you have access to a uranium mine. You can process uranium mining tails for Pa-231, which is a decay product of Uranium-235. It is isotopically pure and can generate a critical mass for fast fission... which means in theory you could make a bomb.
But it would need a lot of uranium ore.
And a reactor is probably cheaper than an enrichment plant, the only ones you can make with unrestricted technology are probably either Calutrons and Gaseous Diffusion.
Those plants would be enormously expensive to ooperate and nearly impossible to keep secret. (What is that plant that is guzzling several gigawatts of electricity?)
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Post by edireland on Jul 8, 2013 21:35:21 GMT 9.5
Magnox is a dual use reactor. B-reactor and the Windscale Piles are examples of how primitive pure bomb creation reactors can be if you are on a shoestring.
You could probably build an entire nuclear weapons programme for less than the price of a two reactor LWR plant if didn't have to worry about keeping the whole thing a secret.
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